STATE PLANE COORDINATES Washington State

1 STATE PLANE COORDINATESW ashington StateWashington STATE Land Surveyors AssociationLarry Signani13 March 2007 SURVEY TYPES Surveys can be grouped into two categories: 1. PLANE Surveys 2. geodetic SurveysA survey of a small area in which the area surveyed is considered flat except for topographic variations, is termed a PLANE survey and this branch of surveying is called PLANE Surveying,.When a survey covers a large portion of the earth, the curvature of the earth has to be considered. Surveys of this type cannot be mapped on PLANE sheets of paper without distortions.

2 These are called geodetic Surveys, the position of points are indicated either by spherical COORDINATES , namely Latitude and Longitude, or by PLANE COORDINATES after projecting onto a plan surface, , STATE PLANE COORDINATES SURVEY TYPES PLANE Surveys-assume earth s surface is flat PLANE -use X-Y COORDINATES -easy procedures and computations-sufficient for most surveys geodetic Surveys-accurately represent earth s shape-use spheroid COORDINATES (Latitude, Longitude)-more complex, expensive, difficult computationsGEOCENTRIC AND GEOGRAPHICALLATITUDE & LONGITUDETHE ELLIPSOIDMATHEMATICAL MODEL OF THE EARTHbaa = Semi major axisb = Semi minor axisf = a-b= FlatteningaNSTHE ELLIPSOIDUNITED STATESELLIPSOID DEFINITIONSCLARKE 1866a = 6,378, m 1/f = REFERENCE system 1980 - (GRS 80)a = 6,378,137 m 1/f = geodetic system 1984 - (WGS 84)a = 6,378,137 m 1/f = 1841a = 6,377, m 1/f = ELLIPSOID(1738)6,397,3006,363, (1830)6,377, ,356, (1866)6,378, ,356, AmericaClarke(1880)

3 6,378, ,356, , AfricaHelmert(1969)6,378,1606,356, AmericaWGS-72(1972)6,378,1356,356, (1979)6,378,1376,356, 83(1982)6,378,1376,356, AmericaWGS-84(2003)6,378, ,356, ITRSTHE GEOID AND TWO ELLIPSOIDSGRS80-WGS84 CLARKE 1866 GEOIDE arth MassCenterApproximately236 metersDATUMSA set of constants specifying the coordinate system used for geodetic control, , for calculating COORDINATES of points on the Earth. Specific geodetic datums are usually given distinctive names. ( , North American Datum of 1983, European Datum 1950, National geodetic Vertical Datum of 1929)DATUMVERTICAL DATUMSMEAN SEA LEVEL DATUM OF 1929 NATIONAL geodetic VERTICAL DATUM OF 1929(As of July 2, 1973)NORTH AMERICAN VERTICAL DATUM OF 1988(As of June 24, 1993)

4 NGVD 29 and NAVD 88 COMPARISON OF VERTICAL DATUM ELEMENTSNGVD 29 NAVD 88 DATUM DEFINITION 26 TIDE GAUGES FATHER S POINT/RIMOUSKI IN THE & CANADA QUEBEC, CANADABENCH MARKS 100,000 450,000 LEVELING (Km) 102,724 1,001,500 GEOID FITTING Distorted to Fit MSL Gauges Best Continental ModelCOMPARISON OF DATUM ELEMENTSNAD 27 NAD 83 ELLIPSOID CLARKE 1866 GRS80a = 6,378, m a = 6,378,137.

5 M1/f = 1/f = POINT Triangulation Station NONEMEADES RANCH, KANSAS EARTH MASS CENTERADJUSTMENT 25k STATIONS250k STATIONSS everal Hundred Base Lines Appox. 30k EDMI Base LinesSeveral Hundred Astro Azimuths 5k Astro AzimuthsDoppler Point PositionsVLBI VectorsBEST FITTING North America world -WideNAD 27 and NAD 83 HIGH ACCURACY REFERENCE NETWORKS GPSABLE Clear Horizons for Satellite Signal AcquisitionEASY ACCESSIBILITYFew Special Vehicle or Property Entrance RequirementsREGULARLY SPACEDA lways within 20-100 KmHIGH HORIZONTAL ACCURACYA-Order (5 mm + 1:10,000,000)B-Order (8mm + 1.)

6 1,000,000)HIGH ACCURACY REFERENCE NETWORKSHARNHARNTHE GEOIDGRID AZIMUTH COMPUTATION g = A+ Laplace Correction - = 253o 26 (Observed Astro Azimuth)+ ( ) (Laplace Correction)= 253o26 ( geodetic Azimuth)-0 36 (Convergence Angle)= 252o49 The convention of the sign of the convergence angle is always from Grid to GeodeticUNDULATIONS OF THE GEOIDUNDULATIONS OF THE GEOIDELLIPSOID -GEOID RELATIONSHIPHhEllipsoidGRS80H = Orthometric Height(NAVD 88)NGeoidH= h - NPERPENDICULAR TO ELLIPSOIDPERPENDICULARTO GEOID (PLUMBLINE)DEFLECTION OF THE VERTICALDEFLEC99 TOPOGRAPHIC SURFACEh = Ellipsoidal Height (NAD 83)N = Geoid Height (GEOID 99)GEOID99 STATE PLANE CoordinatesBRIEF HISTORY:-Originally a English unit grid system -Developed by land surveyors in the 1930 s to simplify surveying computationscooperative venture between the Coast and geodetic Survey and the North Carolina STATE government, and efforts to build a North Carolina spatial coordinate systemwith minimaldistortion was started.

7 In 1933 this cooperative venture produced the North Carolina Coordinate system . In less that 12 months, the North Carolina system had been copied into all of the remaining states , and the STATE PLANE coordinate system was only in the USSTATE PLANE COORDINATE SYSTEMSL ambert Conformal Conic and Transverse Mercator ProjectionsInternational, STATE and County BoundariesNAD 27 - COORDINATES in Survey FeetNAD 83 - COORDINATES Metric w/ STATE Defined Foot Conversion1 Meter = Survey Feet1 Meter = International Feet NAD 27 to NAD 83 VERY large Positional ShiftsTypes of PLANE SystemsPlaneEllipsoidTangent PlaneLocal PlanePoint of OriginIntersecting CylinderTransverse MercatorAxis of EllipsoidEllipsoidAxis of CylinderStandard ParallelsApex ofConeIntersecting Cone2 Parallel LambertAxis of Cone & EllipsoidEllipsoidLAMBERT CONFROMAL CONICWITH 2 STANDARD PARALLELSA pproximately

8 158 milesCENTRAL MERIDIANSTANDARD PARALLELS 0 Earth Centera b abcdc d geodetic vs. GRID DISTANCEab > a b cd < c d LAMBERT CONFROMAL CONICWITH 2 STANDARD PARALLELSCENTRAL MERIDIANSTANDARD PARALLELS n s 0 SCALE EXACTSCALE EXACTSCALE < 1 SCALE > 1 SCALE > 1 Grid Scale FactorStandard ParallelsTRANSVERSE MERCATORCENTRAL MERIDIAN 0 SCALE EXACTSCALE < 1 SCALE > 1 SCALE > 1 STATE PLANE COORDINATE SYSTEMSN orth and South ZonesS. Zone Origin 45-20/120-30N. Zone Origin 47-00/120-50N=0m, E=500,000mN=0m, E=500,000m47-3048-4445-5047-20 Washington ZONESPARAMETERS OF A LAMBERT PROJECTIONRCW RCW Definitions.

9 Unless the context clearly requires otherwise, the definitions in this section apply throughout RCW :(1) "Committee" means the interagency federal geodetic control committee or its successor;(2) "GRS 80" means the geodetic reference system of 1980 as adopted in 1979 by the international union of geodesy and geophysics defined on an equipotential ellipsoid;(3) "National geodetic survey" means the national ocean service's national geodetic survey of the national oceanic and atmospheric administration, United states department of commerce, or its successor;(4) " Washington coordinate system of 1927" means the system of PLANE COORDINATES in effect under this chapter until July 1, 1990, which is based on the North American datum of 1927 as determined by the national geodetic survey of the United states department of commerce.

10 (5) " Washington coordinate system of 1983" means the system of PLANE COORDINATES under this chapter based on the North American datum of 1983 as determined by the national geodetic survey of the United states department of commerce. [1989 c 54 9.]RCW RCW system designation Permitted uses. Until July 1, 1990, the Washington coordinate system of 1927, or its successor, the Washington coordinate system of 1983, may be used in Washington for expressing positions or locations of points on the surface of the earth. On and after that date, the Washington coordinate system of 1983 shall be the designated coordinate system in Washington .